Control for electric flatirons



CONTROL FOR ELECTRIC FLATIRONS rf/Z H6 6 :Jn/vento@ JOHN HARPER.

Chroma? Passieaiuiy 5, 1927.

f .ionulmrnng or ronrLAND/oniieon.

Paii-:NTI "oi-"Fic-E.

" eoiriinor.l ronnnnc'rmc Fmrmons.

y' lapplicaties vinea Apfrii 29, 1925. senin` mi. 26,643.

kThis inventionrelates generally' /fto electric fla't irons, and particularly to means for con-` y trolling the temperature of the iron.

forni of circuit-making an ci f ' when .the iron kreac moveiijient of a thermostat.y 'y l u f p The fourth object is'to so construct the de- I The first yobject ofy this inventiony is to s provide an ex'ceedinglysimple and eicient control iforthe 'temperature of an iron which will cut 'oft' the supply ofelectricalenergy ies the maximum temperature desired, and to restore ythe supply when the temperature falls` below a given f point.

The second object` y is' toy eliminate Ithe dangers from fires causedfbyfthe users of i, y

clamps 27 and 27A-'to which are attached the electric irons leavingsame with the Acurrent turned on thereby permitting same to 'be over-heated and ignitiiig surroundingobjects. y j

'The third object is to irovide a special d breaking device whereink the making andv breaking of the circuit is made witha relatively rapid movement whencompared with the ordinary slow vice that it will readily respond to .changes of teniperatui'e in tliefiron and that it will be ofk a nature 'which' [will permit its 'installation in almost any type of iron vwith #only a relatively small change'being made cuit broken.

therein. v

` y'Figure lisa vertical section through the device taken along the line 1 `1` in Figure 3. Figure 2 is a' verticaly section taken'along thefline 2-f-2f'inFigure 3. Figure. 3'is a n' transverse verticalsection taken along the line in Figure 1. .Figure 4 is a` fragmentaryvei'tical section similar` to tlielup-` per portion 'of Figure .1 showing tlie'cir- Figure 5k lis a fragmentary vertical section similar 'to the upper portion of Figure 2 showing the osition ofthe arts, also vduringfthe/time w en the circuit is open. Figure 6 is ra rear elevation for a flat iron showing the device attached and Figure 7'is a side elevation thereof.

Similar numbers of reference refer vto the same parts throughout the several views.

Referring in detail to the drawing, there is shown for the purpose ofk illustration an electrical Hat iron 10 provided with the usual handle 11 and a receptacle 12, which receptacle in thisy case` must be slightly enlarged. In the receptacle are-the usual contact posts 13 common tomost' electric irons.

'In the top `of the iron is provided an opening 14 through which heat passes to the 22Ywh`ich is directly over t-lie opening 14 in the yironlO. A second pair of openings 23 kand 24 register with the contact posts 13.

Inenlarged portions of the openings 23 are placed the insulating bushings 25 and 26, in which are housed the U-sliaped contact wires28 and 29 by means of the screws 30. Above the member 21 and journaling in cups 3l, which are vmounted in the bosses 32 oii the inner sides of the members 15 and 16, are the pivots 33 alid 34. The, piv0t'34 is mounted on the side of the U-shaped housing 35 whose ends 36 are attached by means ot the screws 37 to a disk 38 which is prof vided with openings 39 and' 40.

A mercurial thermometer consisting' of the lower4 bulb 41,`which is placed within the opening 39,y an upper bulb 42 in the opening 40 and a connecting` tube 43. A quantity of mercury 44 is placed in the lower bulb 41.

A pair of straps 45 are placed around the tube l43 and are held by mea'ns'of thefscrews 46 to the disk 38. A central strap 47 isattached tothe disk 38 bymeansI of the screws 48 and this strap carries the pivot 33.y

Between the end walls'36 is placed the cylindrical container 49, preferably made of glass, andv mounted concentricirlly with the pivots 33 and 34 between the curved blocks 50 against the members 36. Aquantityof mercury 51 is placed in the container 49 and the space unoccupied bv'the mercury 51 is filled with inert gas.

In Athe upper side of the member49 are introduced the two electrodes 52 and 53 which are adapted to dip slightly into the mercury 51 when the bottoms of the two electrodes are level.l Flexible lead wires 54 and 55 connect the wires 28 and 19 with the electrodes 52 and 53. f

A portion of the disk 38 is turned outwardly to form a lug 56 through which is passed a radial'screw 57 whose head passes through a slot 58 in the top 17. Screws 59 are employed to hold the cover 16 in place on the outer shell 15.

The operation of the device is as follows:

When starting to iron, the parts take the position shown in Figures 1, 2 and 3 and current flows between the electrodes 52 and 53 to the heating elementin the iron. lVhen the temperature of the iron rises sufficiently and heat passes upwardly through the open ing and reaches the thermometer bulb 41, the mercury therein is forced to rise in the tube 43 and enters the bulb 42, thereby unstabilizing the rotatable parts which are mounted on the pivots 33 and 34. The screw 57 tends to unbalance these parts and causes same to take the positions shown in Figures 4 and 5 wherein it will be seen that the electrode 52 will be raised out of the mercury 51, thereby interrupting the flow of current to the iron. This condition will remain until the temperature of the iron drops suiliciently to allow the mercury to descend into the bulb 41, thereby increasing the stability l of the rotatable parts causing both of the electrodes 52 and 53 to touch the mercury 51 and restore the flow of current to the iron. It will be noted that the thermometer .bulb 41,' with the tube 43 and the bulb 42, are

made somewhat adjustable within the o enings 39 and 40 in order to permit the est position for these parts. It is evident that the screw 57 can be adjusted from the exterior of the top 17 and that this adjustment will affect the temperature at which the circuit is closed or opened by the device.

It must be understood that it 1s not my intention to confine myself to this precise form or construction of parts, as many changes can be made in the details of this device without departing from the spirit of my invention.

I am aware that many forms of controls for electric flat irons have been constructed in the past; I therefore do not intend to cover same broadly but I do intend to cover all such forms and modifications thereof as fall fairly within the appended claims.

I claim:

1. A temperature controlled switch havingv on'said disks; la pair of spaced electrodes normally `touching the mercury in said container; andl means for unbalancing said disk 'having an adjustable weight mounted thereon adapted to imbalance same when the mercury rises into said overflow bulb.

3. A thermometer-controlled mechanism consisting of a mercury container having pivotal supports and having its bottom concentric with said pivots; mercury in said container; a pair of spaced electrodes mounted on said container and normally touching said mercury; a thermometer rotatable with said container and having its mercury containing bulb slightly below the axis of said container, said thermometer having an overflow bulb above said axis; and adjustable means for rotating said parts after they have been unbalanced by the mounting of the mercury into the overflow bulb.

4. A thermometer controlled switch consisting of a casing having an opening therein adapted to communicate with a heated area; a mercury container pivotally mounted within said casing'having the lower side of its mercury-engaging with said pivots; a pair o electrodes mounted on said container normally touching said mercury; a thermometer rotatably mounted with said container over said heat-conveying opening and having .an overflow bulb on its upper end, said thermometer serving to unstabilize said container when the mercury in said thermometer rises; and means for rotating said container consisting of a radial screw `also adapted to act as a stop for the rotary movement of said container.

JOHN HARPER.

switching ortion concentric f 

